Influência de diferentes tipos e proporções de aglutinantes nutritivos na estabilidade física de rações orgânicas peletizadas para peixes.

Abstract

In aquaculture, as less is the diet leaching and dissolution in water, greater will be it's use by fish and lower the pollution of aquatic ambient. Therefore, the addition of binders are recommended and can directly influence the diet stability. In this sense, the present study aimed at evaluating the influence of three types of nutritional binders (maize, wheat flour and wheat bran), added in different proportions in the formulation in order to verify the physical stability and the cost of organic handmad diet for fish. Six isoproteic (36% CP), isolipidic (8.4% Lip.) and approximately isocaloric (3330 kcal/kg) organic diets were prepared. They contained in its basal formulation fishmeal and soybean meal as protein ingredients, premix mineral/vitaminic, soybean oil and as nutritious binders the following ingredients and proportions were tested: 100% corn flour; 100% wheat flour; 100% wheat bran; 50% corn + 50% wheat flour; 50% corn + 50 % wheat bran and 50% wheat flour + 50% wheat bran. The variables analyzed were the maximum time floating of the pellets, maximum turgidity time, maximum time of pellet aggregation and leaching of dry matter. Among the nutritional binders evaluated, corn proved to be the most appropriate for inclusion in pelleted diets for fish because promoted good physical characteristics to the feed and showed better cost. The wheat flour has proven to be a great binder, however, the inclusion of this ingredient resulted in increase of diet cost. The wheat bran, although more affordable, presented limitations of use due to its high fiber content, which resulted in diet physical stability losses.